Light emitting diodes (LEDs) are well-known semiconductor devices that convert current into light. The color of the light (wavelength) emitted by an LED depends on the semiconductor materials used. Gallium-Nitride (GaN) has gained much attention, because it is found that GaN can be combined with indium to produce InGaN/GaN semiconductor layers that can emit green, blue, and ultraviolet light. This wavelength controllability enables an LED semiconductor designer to tailor material characteristics to achieve beneficial device characteristics. Accordingly, GaN-based opto-electronic device technology has rapidly evolved since their commercial introduction in 1994.
Light emitting diodes (LEDs) based upon gallium nitride (GaN) are expected to be used in future high-efficiency lighting applications, replacing incandescent and fluorescent lighting lamps. Current GaN-based LED devices are prepared by heteroepitaxial growth techniques on foreign substrate materials. A typical wafer level LED device structure may include a lower n-doped GaN layer formed over a sapphire growth substrate, a single quantum well (SQW) or multiple quantum well (MWQ), and an upper p-doped GaN layer.
Micro-LED, also known as microLED, mLED or μLED, is an emerging flat panel display technology. Micro-LED displays have arrays of microscopic LEDs forming the individual pixel elements. Compared to the widespread LCD technology, micro-LED displays offer far greater contrast, much faster response times, and would use less energy
Conventionally, during the in micro-LED manufacture, RGB pixel is provided and manufactured one by one. Since this process takes longer time, for mass production, more efficient and faster manufacturing method is required.